The function of CYP2A6 (cytochrome P450 family 2 subfamily A member 6, ENSG00000255974) is as follows. Exhibits a high coumarin 7-hydroxylase activity. Can act in the hydroxylation of the anti-cancer drugs cyclophosphamide, ifosphamide and tegafur. Competent in the metabolic activation of aflatoxin B1. Constitutes the major nicotine C-oxidase. Acts as a 1,4- cineole 2-exo-monooxygenase. Possesses low phenacetin O-deethylation activity. {ECO:0000269|PubMed:11695850, ECO:0000269|PubMed:12042667, ECO:0000269|PubMed:16086027, ECO:0000269|PubMed:17125252, ECO:0000269|PubMed:18779312, ECO:0000269|PubMed:1889415, ECO:0000269|PubMed:1944238}.